SOLVED Frequency keeps temporarily dropping to 3.2 Ghz from 4.5 Ghz

[Rylo]

I overclocked my i7 3930k up from 3.2 GHz to 4.5. I've got a Gigabyte X79-UD3 motherboard with the latest beta bios (F12p) and all I did to overclock was change the multiplier from 35 to 45 and increase the voltage to 1.34 volts (per Intel's 3930k info page). I also changed XMP settings to 'Profile 1'.

I'm still experimenting with voltages (trying to go as low as possible) but one thing that seems to keep happening --- regardless of my voltage --- is that after about 5 minutes of running Prime 95 CPU-Z will show the frequency drop from 4500 MHz down to 3200 MHz for about 5 seconds, then jump back up to 4500. This seems to happen once every 30 seconds or so. While this is happening, the Task Manager window in Windows 8 always shows 99% utilization, which then returns to 100% with the return to 4.5 GHz.

The only other problem I'm having has been blue-screening with the error "clock watchdog timeout", but I assume this is from having the voltage too low as I try to find that sweet spot.

Aside from the settings I listed above, I didn't touch anything else in my Gigabyte bios. It's all set to the default settings (mostly 'auto'), so things like TurboBoost are on.

Thanks!

 

[REX_FX6100]

Your dropping because of the turbo boost. When you begin to overclock you need to disable all turbo boost type options and also all power saving options as well.

 

[Rylo]

Your dropping because of the turbo boost. When you begin to overclock you need to disable all turbo boost type options and also all power saving options as well.

As soon as I disabled TurboBoost (along with the other power saving stuff) my core speed in CPU-Z is 3200 MHz, as if I hadn't overclocked at all.

 

[Boulard83]

Dont disable turbo boost. But you can disable powersaving features when OCing to prevent clock from droping. I leave powersaving on for my 24/7 OC in order to .... save power and heat when computer is idling or doing light task. You dont need to run your CPU at full speed all the time.

If you bench or really want your clock to stay at full speed, disable power saving.

 

[REX_FX6100]

Well if he wants his cpu to stop throttling down he needs to turn off turbo boost....I guess I should have been more clear. The fact that your frequencies are dropping is fine, when the need arises for the top speeds your cpu will bump up the speed. When your idling you don't need full speed and therefore your freq. will drop, that's perfectly normal and there's nothing wrong with how you have your speeds running. The blue screens however will need to be handled appropriately and it sound like you know what to do there already. I would suggest running a stress test for around an hour or more to ensure a little stability.

 

[REX_FX6100]

As soon as I disabled TurboBoost (along with the other power saving stuff) my core speed in CPU-Z is 3200 MHz, as if I hadn't overclocked at all.

I didnt see this before i just posted...thats a bit strange. what are you using to overclock?

 

[Rylo]

Well if he wants his cpu to stop throttling down he needs to turn off turbo boost....I guess I should have been more clear. The fact that your frequencies are dropping is fine, when the need arises for the top speeds your cpu will bump up the speed. When your idling you don't need full speed and therefore your freq. will drop, that's perfectly normal and there's nothing wrong with how you have your speeds running. The blue screens however will need to be handled appropriately and it sound like you know what to do there already. I would suggest running a stress test for around an hour or more to ensure a little stability.

My issue is that it isn't throttling to 3200 Mhz at idle, it's doing it about 5 minutes into a Prime 95 test. Basically, CPU utilisation drops from 100% to 99% (as shown in the Windows 8 task manager) and CPU-Z shows core frequency dropping from 4500 MHz to 3200 MHz (which is this chip's stock speed). It'll sit like that for 5-10 seconds, then bounce back up to 100% utilisation and 4500 MHz. Just thought I'd be clear that this isn't while idle.

Temps are fine the entire time, CPUID Hardware showing 66-73 degrees Celsius.

If this is normal then I won't worry. I seem to be stable with 1.335V at 4.5 GHz, so I'm hoping I'm able to keep my voltage this low.

Thanks for the replies, guys.

 

[Rylo]

I didnt see this before i just posted...thats a bit strange. what are you using to overclock?

Just the Gigabyte bios.

 

[Boulard83]

If this occur when P95 is switching form a calculation to another calculation, its normal.

As for turbo, you need to leave it on in order to OC...

 

[bmwbaxter]

That to me sounds like thermal throttling caused by your vrm section. Point a fan at your power section and it shouldn't throttle.

 

[Boulard83]

That to me sounds like thermal throttling caused by your vrm section. Point a fan at your power section and it shouldn't throttle.

+1, also possible.

 

[Rylo]

That to me sounds like thermal throttling caused by your vrm section. Point a fan at your power section and it shouldn't throttle.

Is there any way I could verify this other than by adding a fan? I haven't increased the voltages on anything except Vcore, and CPU temps are maxing out at 71-73.

Any way to see VRM temps in a utility like Core Temp or CPUIDHM (or other software)?

 

[Rylo]

Also, should I be adjusting any of the other voltage settings? I just left them to auto, but I've been getting bluescreens at odd times (not during full load, for example).

 

[EarthDog]

That to me sounds like thermal throttling caused by your vrm section. Point a fan at your power section and it shouldn't throttle.

this. X79 almost requires it on a lot of boards.

 

[Rylo]

this. X79 almost requires it on a lot of boards.

Any good guides for installing VRM fans? I've got a Fractal R4, so I guess just putting a side fan on wouldn't help much.

 

[Knufire]

Is there any way I could verify this other than by adding a fan? I haven't increased the voltages on anything except Vcore, and CPU temps are maxing out at 71-73.

Any way to see VRM temps in a utility like Core Temp or CPUIDHM (or other software)?

Touch the VRM heatsink. If it's too hot to touch, it's too hot.

As for mounting a fan, easiest way is to get a small 40mm fan and zip tie it on.

 

[Boulard83]

I had a RIVE in a corsair 600T and this is how i oriented some airflow to the motherboard VRM's. The 2 top fan are intake and angled toward the VRM's area. I simply used some spacer on 2 of the fan screw.

Im currently running on a testbed, EZer to cool the VRM's now

 

[Rylo]

Thanks guys. I got a new top-mounted cooler and added two more fans and it hasn't down-clocked since. I really appreciate it!

 

[bmwbaxter]

Thanks guys. I got a new top-mounted cooler and added two more fans and it hasn't down-clocked since. I really appreciate it!

Glad it is working for you

 

[Boulard83]

Good !